VascuBone project develops toolbox for personalised bone
17 November 2014
The EU-funded VascuBone project has developed a "toolbox" that
doctors can select from to regenerate bone for three types of bone
defects. The tool
box includes a variety of biocompatible biomaterials and cell types,
FDA-approved growth factors, material modification technologies,
simulation and analytical tools such as molecular-imaging-based in
vivo diagnostics. These can all be combined for the specific
medical needs of the patient.
Bone is one of the most frequently transplanted tissues and the
demand is rising. Transplants treat large defects like those caused
by trauma, complicated fractures, tumour resection or osteoporosis.
Conventionally, a piece of bone is transferred from one body site to
another of the same patient. But this has the disadvantage of
causing a defect in an otherwise healthy part of the body. Using
bone obtained from a donor also has side effects, such as
immunogenic reactions. New methods are thus needed to meet the
growing demand. The tools developed and optimised in the project are
aimed at helping to overcome these existing shortcomings.
The project is due to complete in December 2014, when it will be
holding its final meeting to report the latest achievements. In the
previous year of the project researchers tested the biocompatibility
of CeraSorb scaffolds (a tricalcium phosphate preparation) modified
by hydrophilic diamond particles and polyester co-polymer scaffolds
developed by the consortium and modified by nano diamond particles.
For evaluating the biomaterials, the project developed various
MRI contrast agents based on fluorine compounds, a Gadolinium-based
polymer and superparamagnetic iron oxide (SPIO) nanoparticles. These
provide information on the structure of the scaffolds and blood flow
in regenerating bone and biomaterials.
The project also developed a sensitive and non-invasive method
for screening the tumorigenic potential of the scaffolds intended
for bone regeneration using high potency bioluminescence (BLI)
in vivo imaging.
“We would like to include everything in our toolbox that is
necessary to put together the ideal therapy for a patient”, says
project coordinator Heike Walles, Professor of Tissue Engineering
and Regenerative Medicine at the University Hospital of Würzburg and
also head of the Oncology Group at the Fraunhofer Institute IGB in
Walles previously developed a three-dimensional scaffold derived
from a piece of pig bowel that contains structures supporting the
development of blood vessels. Different types of adult stem cells,
for example, so-called mesenchymal cells derived from bone marrow,
are supposed to grow on such scaffolds to form the bone substitute.
"These cells are even present in old people,” Walles tells
youris.com. While the cells’ potential decreases with age, “they are
still there and are able to regenerate“, she explains. “But they
have to be enriched, which is increasingly difficult with increasing
age,” she continued.
In the current project, researchers therefore analysed how age
influences the stem cells’ properties. They identified markers that
indicate whether the cells are suited for therapeutic use. They also
looked at other types of cells, so-called endothelial cells. These
may be necessary for treating very large bone defects.
“We analysed which cell type is ideal for therapeutic purposes,
such as microvascular endothelial cells or endothelial progenitor
cells, a stem cell type that can be found in the blood”, said Walles.
Cornelia Kasper, professor for biopharmaceutical technology at
the University of Natural Resources and Life Sciences in Vienna,
Austria, welcomes the toolbox approach: "It offers a combination of
matrix, cells, bioreactors and automated systems, which can be used
to grow tissue under controlled conditions."
Researchers "look for biological alternatives to screws, nails
and titanium plates, particularly for treating defects larger than
three centimetres," she said. Providing scaffolds with vessel
structures for regenerating large bone defects is "something special
and unique," she added.
Kaspar believes using stem cells from the patient’s own fat
tissue or bone marrow and from the umbilical cord offer a huge
potential for bone regeneration and has various advantages.
"Particularly, mesenchymal stem cells are easily accessible," she
said. There are no ethical concerns attached to using such cells and
there are no immunogenic side effects. What is more, these cells
exist in everyone. “Even slim or old patients have fat tissue,” she
She also hoped that such engineering based solutions will be more
widely approved and available for patients within the next five to
ten years. In her view, it is up to politics and the regulation
authorities “to create the prerequisites for a comprehensive patient
care“. But the cooperation between life scientists, engineers and
medical scientists "still remains a real challenge", she concluded.
Heike Walles, discusses the project aims.
The VascuBone Project:
Source: Based on article on Youris.com:
Healing bone defects using regenerative medicine